I was passing through TN today on the west side of Nashville. I saw a state trooper that had three boxes mounted on the trunk. They were about 4 x 4 x 6~8. The one on the passenger side looked to be pointing about 45 degrees to the side and front. The other two on the drivers side I think were pointed to the rear at an angle. One looking like it had a glass or plastic lens. Any idea what the deal is with those boxes? There appeared to be a regular radar antenae mounted on the dash.